Dissector #1: ______________________ Dissector #2: _____________________ Recorder: ____________________

Supervisor: ________________________ Substitute: ______________________ Substitute: ___________________

Fetal Pig Dissection:

External Anatomy1. Determine the sex of your pig by looking for the urogenital opening. On females, this opening is located near the anus. On males, the opening is located near the umbilical cord.

If your pig is female, you should also note that urogenital papilla is present near the genital opening. Males do not have urogenital papilla.

Both males and females have rows of nipples, and the umbilical cord will be present in both.

Is your pig male or female? ___________

2. Make sure you are familiar with terms of reference: anterior (toward the head), posterior (toward the anus), dorsal (back), ventral (underneath side). In addition, you'll need to know the following terms

Medial: toward the midline or middle of the body Proximal: close to a point of referenceLateral: toward the outside of the body Distal: farther from a point of reference

3. Observe the toes of the pig. How many toes are on the feet? ___________________Do they have an odd or even number of toes? _________________

4. Observe the eyes of the pig. Carefully remove the eyelid so that you can view the eye underneath. Does it seem well developed? __________ Do you think pigs are born with their eyes open or shut? __________

As you identify all of the parts of the pig (bold words throughout the packet) put a check on each line or in each box after everyone in your group has seen this part. 5. Carefully lay the pig on one side in your dissecting pan and cut away the skin from the side of the face and upper neck to expose the _____masseter muscle that works the jaw, ____lymph nodes, and _____salivary glands, (put a check on the line after you have located it each bold word). The salivary glands look kind of like chewing gum, and are often lost if you cut too deeply.

6. Open the pig's mouth and locate the _____hard and _____soft palate on the roof of the mouth. Can you feel your own hard and soft palates with your tongue? _______

Note the taste buds (also known as ______sensory papillae) on the side of the tongue. the edge of the mouth for teeth. Does the fetal pig have teeth? ________ Are humans born with teeth? ___________

7. Examine the pharynx which is the cavity in the back of the mouth. To do this you will need to cut the muscle tissue along the jaw and crack the jaw bone by carefully placing your thumbs inside the pigs mouth, one on the soft palate and one on the tongue, pull apart until you hear it crack. The ______pharynx is the junction of the _______esophagus (which carries food to the stomach) and the ______trachea (which carries air to the lungs). Locate the _______epiglottis, a cone-shaped structure at the back of the mouth. What is the function of the epiglottis? _____ ______________________________________

Pig Picture 1

Email Photo with Labels to msleyda1@gmail.comTitle: PigPic1-Per ___ Lab ___ Structures to Label: Epiglottis, Salivary glands, soft palate, hard palate, taste buds, pharynx

Digestive System

In this activity, you will open the abdominal and thoracic cavity of the fetal pig and identify structures. Remember, that to dissect means to "expose to view" - a careful dissection will make it easier for you to find the organs and structures. Be sure to follow all directions.

The Incision: Place your fetal pig in the dissecting pan ventral side up. Use string to "hog-tie" your pig so that the legs are spread eagle and not in your way. Use scissors to cut through the skin and muscles according to the diagram. Do not remove the umbilical cord. In the first section, you will only examine the abdominal cavity (the area below the ribcage). Try not to cut the inner organs while making the incision. After completing the cuts, locate the _______umbilical vein that leads from the umbilical cord to the liver. You will need to cut this vein in order to open up the abdominal cavity. Pin the skin and muscle to the side so that the internal organs are visible. Your pig may be filled with water and preservative, drain over the sink if necessary and rinse organs.

1. Diaphragm. This muscle divides the thoracic and abdominal cavity and is located under the ribcage. The diaphragm aids in breathing.

2. Liver. This structure is lobed and is the largest organ in the body. The liver is responsible for making bile for digestion.

3. Gall bladder. This greenish organ is located underneath the liver; the bile duct attaches the gall bladder to the duodenum. The gall bladder stores bile and sends it to the duodenum, via the bile duct.

4. Stomach. A pouch shaped organ that rests just underneath and to the pig's left. At the top of the stomach, you'll find the esophagus. The stomach is responsible for churching and breaking down food.

5. The stomach leads to the small intestine, which is composed of the ___duodenum (straight portion just after the stomach) and the____ ileum (curly part). The ileum is held together by ____mesentery (thin clear tissue/ membrane). In the small intestine, further digestion occurs and nutrients are absorbed through the arteries in the mesentery.

6. Pancreas: a bumpy organ, probably white in color, located along the underside of the stomach, a ______pancreatic duct leads to the duodenum. The pancreas makes insulin, which is necessary for the proper uptake of sugars from the blood.

7. Spleen: a flattened organ that lies across the stomach and toward the extreme left side of the pig. The spleen stores/breaks down red blood cells. It looks like a little tongue stuck to the stomach.

8. Large intestine: At the end of the ileum (small intestine), where it widens to become the large intestine, a "dead-end" branch is visible. This is the cecum. The cecum helps the pig digest plant material and is the beginning of the large intestine. (you can possibly see little appendix hanging off)

9. The large intestine can be traced to the ____rectum. The rectum lies toward the back of the pig and will not be moveable. The rectum opens to the outside of the pig, or the _____anus. The large intestine reabsorbs water from the digested food; any undigested food is stored in the rectum as feces.

Locate each of the following organs below, check the box when you have located the structure.

Pig Picture 2Email Photo with Labels to msleyda1@gmail.comTitle: PigPic2-Per# ___ Lab #___ Structures to Label: Diaphragm, gall bladder, liver, stomach, pancreas, spleen, large intestine, small intestine

Carefully remove and examine each of the following structures:

1. Remove the stomach by cutting it transversely (crosswise) across the esophagus and duodenum. Make a longitudinal (lengthwise incision along the stomach so that you can open it and view the inside. There are two important valves in the stomach: the ___cardiac sphincter (located at the anterior end) and the ____pyloric sphincter valve (located at the posterior) end. These valves open and close to allow food into and out of the stomach. When the cardiac sphincter does not do its job, stomach acid bubbles up into the esophagus causing ‘heart burn’.

2. Remove the small intestine and carefully cut the mesentery (clear membrane) so that the intestine can be stretched and measured. Note the arteries located in the mesentery - called ______mesenteric arteries. What is the length (in centimeters) of the small intestine? ______________ (optional, if time)

Urinary and Reproductive Systems---Locate each of the structures below and check the box when you have found them. Make sure to view both the male and female pig.

1. Lying on either side of the spine are two bean shaped organs: the kidneys. The kidneys are responsible for removing harmful substances from the blood; these substances are excreted as urine. Locate the ______kidneys. The tubes leading from the kidneys that carry urine are the _____ureters. The ureters carry urine to the _____urinary bladder - located between the umbilical vessels.

2. Lift the bladder to locate the ____urethra, the tube that carries urine out of the body.

Male1. Find the ____scrotal sacs at the posterior end of the pig, ____testis are located in each sac. Open the scrotal sac to locate the testis.

2. On each testis, find the coiled ______epididymis. Sperm cells produces in the testes pass through the epididymis and into a tube called the _____vas deferens (in humans, a vasectomy involves cutting this tube).

3. The vas deferens crosses over the ureter and enters the ___urethra, which leads to the ___penis. The penis will be located in the flap that has the umbilical cord. Cut away the skin to reveal the penis.

Female4. In the female pig, locate two bean shaped ____ovaries located just posterior to the kidneys.

5. The ovaries are connected to the _____fallopian tubes, which carry eggs from the ovaries to the _____uterus. The uterus looks flat and wavy (scalloped). The uterus is dorsal to the urinary bladder.

6. Trace the uterus to the ___vagina. The vagina will actually will appear as a continuation of the uterus. The vagina and urethra open into a common area called the _____urogenital sinus.

Pig Picture 3Email Photo with Labels to msleyda1@gmail.comTitle: PigPic3-Per# ___ Lab #___ Structures to Label: Kidney, Ureter, Bladder, ColonMales: Testes, epididymis, and Vas DeferensFemales: Ovaries, fallopian tubes, uterusrrLabel the diagrams

Dissection of the Thoracic Cavity Circulatory/ Respiratory System

You may need to cut through the pig's sternum and expose the chest cavity (thoracic cavity) to view. See the diagram to make the incisions. You will need to cut all the way up into the pig's neck, almost to the chin and open the thoracic cavity. Identify each of the following organs.

1. Find the ____diaphragm again. Remember that the diaphragm separates the abdominal cavity from the thoracic cavity and it aids in breathing.

2. Remove the ____pericardium, which is a membrane that surrounds the heart. This membrane is also located over many of the organs and can get in the way of your view.

3. The structures visible on the heart are the left and right ___atrium, the right and left ____ventricles (which has two chambers but the separation is not visible from the outside), and the large Aorta - a vessel which leaves the heart. (more on the heart later)

4. Push the heart to the side to locate two spongy ____lungs located to the left and right side. The lungs are connected to ____bronchial tubes which connect to the _____trachea (forming a Y). If you are careful and do not damage the bronchial tubes you can use a straw to inflate the lungs.

5. The ____trachea is easy to identify due to the ____cartilaginous rings, which help keep it from collapsing as the animal inhales and exhales. The trachea should be located behind the heart and liver and near the esophagus, but note that the esophagus and trachea are separate tubes.

6. Lying ventral to the trachea, locate the pinkish-brown, V shaped structure called the ____thyroid gland. This gland secretes hormones that control growth and metabolism.

7. At the anterior end (toward head) of the trachea, you can find the hard light colored ____larynx (or voice box). The larynx allows the pig to produce sounds - grunts and oinks.

Pig Picture 4Email Photo with Labels to msleyda1@gmail.comTitle: PigPic4-Per# ___ Lab #___ Structures to Label: Thyroid, Larynx, Thymus gland, Trachea, Aorta, Ribs, Lungs, L. Atrium, R. Atrium, L. Ventricle, R. Ventricle

Pig StructuresIdentify each structure on the diagram. For the test: make sure you know the function of each part and what body system it is a part of.

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2.

3.

9.

10.

4.

5. 11.

13.

7.

8.

6.

14.

15.

12.